Starting with kernel 2.6.37-0.slh.1-aptosid-{686,amd64}, the "]ar9170usb" driver, used for Atheros AR9170 USB 802.11 wlan devices, will be replaced by its successor "carl9170". The advantages of using carl9170 over ar9170usb are:

actual support for 802.11n (HT operations)
AP mode
actively maintained and developed